Cast-steel plate for edge-tools



J. LANE. Cast Steel Plates for Edge Tools.

No. 230,948. Patented Aug. 10, 1880.

Wfinesses [ZZZ/W220).

Cam 1 4 Q N-PETER$ FMDTO-UTHOGRAPKER WASHKNGTON u c JOHN LANE, 0F HYDE PARK, ILLINOIS.

tn'l'E FQR EDGE-TOULS.

SPECIFICATION forming part of Letters Patent No. 230,948, dated August 10, 1880,

Application filed November 20, 187.).

To all whom it may concern Be it known that I, JOHN LANE, of Hyde Park, in the county of Cook and State of Illinois, haveinvented a new and useful Improvement in the lllanulacture ot' CastSteel Plates or Bars for cutting implements which have their cutting-edge formed and made from the middle part of the plate or bar; and I do here by declare the following to be a full, clear, and exact description of the same.

My invention relates to plates or bars of caststeel for cuttingimplements, as plowshares, colterblades, cultivator teeth, hay knives, scythes, cornstalk cutters, millstone picks, lmife-blades, and other cutting implements which have their cutting edge forn'ied and made from the middle part of the plate or bar of steel.

, Ileretot'ore such euttin g implements required to be hardened and tempered after bein g formed from the plate or bar, to tit them with suitable hard-tempered cutting'edges, which by my invention is avoided.

The object of my invention contemplates producing plates or bars of cast-steel which shall have a middle section sutlioiently hardtempered not to require further hardening and tempering, and from which tunic-blades and other cuttingimplements may be formed and made without any necessity of hardening and tempering hem to litthem with good cutting-edges, and having exteriors of less hardtcmpered cast-steel for supporting the hardtcmpered middle section from liability to break, and alsoiorproducingaselt sharpening-cutting implement by the exteriors being the softer and wearing away the faster, keeping the thin middle section sharp-cutting by wear in use, and also for producing a superior polish.

My invention consists in interposing a middle-section layer of hard-tempered cast-steel between exterior-section layers of lesshard tempered cast-steel, as hereinafter more fully set forth.

It is well known tempered cast-steel may be made of any desired degree of hardness by the introducing of more or less carbon in the making of the steelthe more carbon in the steel the harder tempered it will be. I take advanta go of this fact in the making of my improved plate or bar of east-steel by adding an extra quantity of carbon to the middle-section strata part of the plate or bar, producing a hard-tem pered cast-steel, which will not need hardening further when being made into cutting implements to equal ordinary cast-steel hardened and tempered.

Reterring to the annexed drawings, Figure 1 gives a view of my improved plate or bar A of cast steel, and Fig. 2 a cross-section view of same on line a of Fig. 1.

The plate or bar A is formed of three layers of cast-steel, making what I call three-ply hard-centercast-steel, the middle part, a, being hard-tempered cast-steel by the combining therewith of an extra quantity of carbon, and the exterior parts, Z) I), at each side of same are of less-hard tempered cast-steel with out the extra quantity of carbon combined therewith.

I prefer a process of making my improved plate or bar of caststecl as follows: I first p repare a block ot'hard-tempcred cast-steel, which has been made by introducing and combining therewith an extra quantity of carbon, which block, properlyprepared, I place in the center of an ingot-mold, when molten cast-steel is then turned in on each side of said block, and uniting therewith in the process of casting, forming an ingot of cast-steel havin a hardtempered middle-section part. The ingot is afterward rolled to desired thickness for plates or bars, from which cuttingimplements are formed and made in the usualprocess of making such, without any need of hardening or tempering in the making of the implement.

In operation, cutting implements formed and made from my improved plate or bar of cast-steel will have avoided all necessity of the process of hardening and tempering in their making, and the exteriors being east-steel instead of iron a better polish, more elasticity, and less weight are secured.

The process of casting molten cast-steel on both sides of a central plate or block in an ingot-mold is not new, and I make no claim to such process, broadly; and I am aware it is not new to make compound blocks or masses of steel of varying temper and hardness by first running the same in a molten condition successively into molds, and by then stampconsisting of strata of cast-steel, tl1e middleing or rolling the same, and-such I do not section part being lmrd-tempercd and the eX- IO claim, broadly.

Having thus fully set forth my invention, I olaim The plate or bar of cast-steel suitable for cutting implements which have their cuttingedge formed from the centerof the bar or plate,

terior-section parts being less-hard tempered, substantially as and for the purpose set forth.

JOHN LANE. Witnesses FRANK M. WILsoN, E. L. LANE. 

